The NLM maintains computer catalogs of its printed, manuscript, and audio-visual holdings (Catline and Avline). A name authority file (Mednam) is maintained to provide control for the personal and corporate name headings used on Catline/Avline records. The History of Medicine Division, which collects and catalogs all material published before 1914 and modern manuscripts, maintains a manual catalog and name authority file for manuscripts and books published before 1801. Until 1981, its records were not input into the computer file. Since 1981, HMD records have been input through retrospective conversion and new cataloging. Because of the various sources from which the data was entered, many duplicate and variant records exist in Mednam, so that a single personal or corporate entity may appear in several forms in Mednam and in Catline/Avline, or on authority records of varying completeness. Through this project, the variants and duplicates will be identified, a single form of each heading will be chosen, all headings in Catline/Avline will be corrected to conform to the authorized form, and duplicate and variant Mednam records will be deleted. In addition, information, such as "see" references and sources, presently existing only on HMD manual records, will be added to the Mednam records. The use of the HMD authority file, consisting of approximately 29,000 records, will be discontinued.